Can testing machine



Nov. 12, 1935. w. CAMERON 2,020,535

' CAN TESTING MACHINE Filed Aug. 9, 1930 5 Sheets-Sheet l Nov. l2, 1935.w` CAMERON C AN TESTING MACHINE Filed Aug. 9, 1930 5 sheets-sheet 2NOV.` 12, 1935. WCAMER0N CAN TESTING MflxCHINE Filed Aug. s, 19:50 5sheets-sheet 5 w, CAMERON Nov. l2, 1935.

CAN TESTING MACHINE Filed Aug. 9, 195o 5 Sheets-Sheet 4 l Nov. 12,1935.e

W. CAMERON CAN TESTING MACHINE Filed Aug. 9, 1930 5 Sheets-Sheet 5'kI'I'hisinvention relates in general machines andparticularly machinesfor testingv ed.- The time interval required for establishingDPfSsrATFEs musas;

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v 2,020,535 can ras'rmo Mac Y WilliamCamex-on, Chicago, Ill., assignerto G- .cron Can Machinery-Co., Chicago, Ill., acorporation of Illinoisitpplicationltugust 9, '1930, Serial No. 474,235

to testing bodies to determine whether or not the bodies 'arafleekproofn bodies haveheretofore been tested by applying `either airpressure or a vacuum 'to the interiorthereof, and the change in pressureor vacuum, as the case might be, within the interior of the can .bodyresulting from a leak in the body was utilized to actuate mechanism forseparatin the leakybodiesram the` goed bodies. l

To diminish the pressure on the interior of a can body sumciently belowatmospheric prsure or to increase the interior pressure to sumcientlyabove atmospheric pressureto operate a leak detecting and canseparatingmechanism has been found in the-past to require .a substantialtime. interval as well as a considerable expense inthe necessary`pneumatic `'equipment because-of the cubical content of the cansordinarily being testa satisfactory test in either of the abovementioned modes would naturally tendrto be increased with the increasein .size of the can bodies and 'would be afactor in every instancetending to retard the speedotesting.

One o'f the objects of this invention is to provide-an apparatus inwhichthe leak detecting mechanism is made responsive not to pressurevariations on the inside of the can bodies as was theprlor practice butto pressure variations in a conned spaceoutsideof the can body of muchsmaller capacity than the can body volume.

Other objects of the `invention are to provide means forattaining thefirst mentioned object with a maximum of accuracy and speed inanabparatus constructed to function efiiciently with the minimumofmaintenance expense.'

Other numerous objects of my invention which are inherently possessed byit should become apparent upon a perusal of this specification and thedrawings which form a part hereof.

In the drawings:

Fig. l is e. vertical sectional view of a can testas viewed from theright end of Fig. 1 showing in section `a. portion of the -leakdetecting mechanism,

. Fig. 4 is a section on the line 4 4 of Fig. 1,

Fig. 5 is a sectional view 'on the line 5--5 of.

s enamel (ci. '1a-5 1) Jing mechanism,

Fig. 48 is an enlarged sectional detail Aview of a y can pocket, and

Fig. 9 is a somewhat diagrammatic description of a modified form of theleak detectingmechanism.

Referring now to the drawings the `machineis provided with a base I onopposite sides of which are mounted standards 2 and 3..w'hich at theirupper ends provide bearings t and 5. .The bear-- if: ing e carriesastationary tubular sleeve 6 While the bearings carriesa stationarytubular sleeve L l, the two sleeves being rigidly aligned and connectedtogether by a `hollow shaft v3` and .clamping nuts, and il. The ends ofthe hollow shaft 8 dit are closed with suitable plugs I 2. A rotatablecarrier for the can bodies while they are being tested is provided inthe form of a large disc wheel gener- I ally indicated as I3 which isrotatably mounted upon the inner end of the shaft l where the hub I@ ofthe disc wheel bears thereon. On the perimen/ ter of the. disc wheel I3there is provided a large ring gear I5 by which rotary motion isimparted to the carrier by means of a lspur gear I6 in i mesh with thering gear and driven by the shaft il on which is secured a second gearI8 in mesh with the gear It, the latter being driven in any suitablemanner as for example by a sprocket chain 2|! connected preferably withan electrical motor (not shown). ad

The shaft i l is suitably supported in the stand- I ard 3 by a bearing22 and carries furthermore a' gear' 23 which through suitably connectedgears (not shown) drives the vshaft 24 on which is' mounted thedischarge wheel 25. Another suitdi able train of gears (not shown)connected with thegear 23 enables that gear to drive ashaft 2t (see Fig.2) on which is fixed the feed wheel 2l.- The rotatable carrier iscomprised of a disc it and radial reinforcing webs 28. Near the per`imeter of the disc there is mounted a plurality of can body pockets 2sinto which the c are placed for pneumatic testing. The mechanism forinserting the cans int@ the pockets and withdrawing them'will now bedescribed.

A pump, not shown, but which may be any pump suitable for the purposeplaces a partial` vacuun through a pipe 3i on the hollow interior 32 ofthe standard 2 (see Fig. 1). The interior of the hollow standard isconnected by means of a? nach: with the me in the hollow shaft 8.Another passage 9| connects the vacuum 'system with a 'chamber 88 whichis provided between the stationary block 81 and the cup-shaped plate 88.The plate 88 is secured in any suitable manner, not shown,'to .the discI8 and rotates vin-position. The chamber 98 which consists ofcooperating recessesin the block 91 and plate 88 extends annularly aboutthe hub i4 of the carrier and is so constructed and shaped as toestablish communication between the source of vacuum and any tube 44thereby, in cooperation -with other parts of the mechanism. applyingvacuum to the interior of each can disposed on the carrier from the'time the can is deposited in`the carrier until just before it isdischarged from the carrier. The approximate extent and cross sectionalshape of the vacuum chamber 98 is indicated by dotted lines in Fig. 2.

Adjacent each can pocket 29 and suitably supported in the carrier disci8 there isa hollow sleeve 41 in which is slidably disposed a hollowshaft 48. 'I'he opposite ends of the shaft 48 are lsealed with suitableplugs 49; vRigidly mounted on one end of the shaft 48, as shown, is achuck head il which carries a hollow rod 52 on which is mounteda chuck82. the face 58 of which is covered with rubber or any other suitableresillent material suitable for establishing a tight sealingcontact withthe open end of a can body and the open end of the can pocket. Passages54, 55 and I8 are in communication with each other and through the portl1 and shaft 48 connect the chuck with the tube 48 by means of theannular passage 88 so that when any tube 48 is in communication with thevacuum chamber I8 the vacuum will be applied to the chuck. When therotation of the carrier disc has carried any one of the tubes 48 beyondthe limits of the annular vacuum chamber I8 such tube will, through itspassage 48', communicate with the passage I9 directly to the atmosphereand thus relieve the vacuum at the chuck. This would be the conditiondesired at the time of releasing a can body and vdischarging it from thecarrier.

When a can has been conveyed into the carrier and aligned in front ofone of the can.pock ets 29 suction is applied at the suction headthrough the above described passages and vacuum chamber 88 and at thesame time the bevel gear 8| becomes engaged with a rack 82, which issuitably supported by a bracket 88 upon the collar 4| and, since therack is stationary and the bevel gear 8i travels with the carrier disc,thegear will be caused to rotate. The gear 8| is mounted on a shaft 84iournaled in bearings 68 and on the other end of the shaft is rigidlyfixed a crank arm 89. This crank arm is lpivotally connected with aconnecting rod 1l, thev latter being in turn pivotally connected withthe chuck head Il. The rack 82 is one of two segmental racks bettershownv in my copending application Serial No. 331,845, illed January 11,l929.- One of the racks 82 is positioned to the left of thel verticalcenter line of Fig. 2 to engage one of the bevel gears 4I immediatelyafter the chuck asy sociated with that bevel gear has pneumatically. vgripped a can body. Theresulting 'rotation of the gear 8i will thencause the connecting rod 1| to movethe hollow shaft 88 to thev right, asviewed g4 in Fig. l, and introduce the can body in to the associated canpocket. 'Ihe othertsegmental rack 82 is positioned to the right of thevertical center line of Fig. 2 to engage each bevel sear'iias l it comesaround to tlnit position to rotate the 10 same and withdraw theassociated can body from the can pocket preparatgry'to its dischargefrom i the testing machine. n tween the positions .ocf cupied by theracks each shaft 84 is held against accidental rotation by means of thesliding con-fu tact of its cam followerl` 12 against the ringA 1I...Details of the construction of the cam follower, o ring and racks arebetter shown in my aforesaidy copending application.

With vacuum applied to ythe interior of each m can which is reposing ina can pocket during almost the entire period of its retention in therotatable carrier any leak however slight can be detected by means ofthelfollowing described mechanism. Each can pocket will be constructedof the pocket and will very'nearly ll the can a0 pocket, leaving howevera small chamber 18 outside of the can body for a, purpose about to bedescribed. The margins of the plate 14 will be provided with flutes 18at intervals to provideA communication between the chamber 18 at the 35lateral sides of the can body and the space 11 between the bottom 18 ofthe-can body `and the' face of the plate 14.A The plate 14 is screwedinto the base of the can pocket and a hollow tube 19 is threaded throughthe central passage in 40 the plate 14 until its end abuts againsttheshoulder 8i in the can pocket, thus locking the plate 14 firmly inposition. By means of the threads provided on the tube 19 vand the plate14 it is apparent that the plate 14 may be adjusted out- 45 wardlysomewhat from the position shown in Fig. 8 and locked in that positionif it is desired to accommodate the testing of a can of somewhat lessheight than usual. With the parts. locked in the position shown in Fig.8 each vpas- 5o sage 82 is in communication with the spaces 11 and 18and communicates with o,l tube 88, the latter being connected to amovable plate 84 and with a radial passage in the movable plate.Alternate tubes are connected to short and long 55 passages, -the longpassages 8l being shown in cross section in Fig. 1, the offset portionof each of these having an aperture 88' which commimicates with the faceof the stationary plate 81. The tubes which are not connected to thelonger 00 passages 88 are connected to shorter passages 88 (see Fig. 4),these passages having apertures 88 which in turn communicate with theface of the stationary plate valve 81. The valve 81 is held in slidingcontact with the plate valve 84 65 by means of a plurality ofcompression springs' 89 which abut against the stationary plate 9|', theplates 81 and 9| being held against rotation by means of a pin 92 whichextends into the sleeve 1. f

Referring now to Figs. 4 and 6, the stationary platev valve 81 isprovided with a pair of arcuate recesses 93 and 94 which are constantlyin communication respectively with passages 98 and 98 which are open'tothev atmosphere. The purpose 75 aoaasss of these recesses'is toestablish atmospheric pressure withinv each canpocket surrounding thecan bodyshortly after a can body has been placed in the testing machine.This is accomplished as follows. The recesses are so placed' that as thecarrier wheel rotates the apertures 96' and 98' which are connected withthe tubesV 83 will successively be brought into communication with theserecesses, the apertures 30' registering with recess 93 andthe apertures88' registering withy recess 94. When this registration is accomplishedand. while it is being maintained the space surrounding each can bodywill be in direct communication through tube 93 with should tend to drawair into the interior of the can body there will be a resultant decreasebelow atmospheric pressure in the space within the can pocketimmediately surrounding the can body.

Assuming that the c an pocket tube ,83 leading from any can pocket haspassed beyond the recess 94 and finally comes around to the position ofthe recess 91 in the. stationary plate A91 com.- munication willimmediately be established from the tube 83, through the passage 88,aperture 88', recess 91 and tube 99 to the leak detector mechanism bestshown in Fig. 3. This mechanism comprises a block 99 secured by thebracket |Ii| to the frame memberd of the machine having 4on either sideof it circular diaphragms |02 and |03 which are secured by means ofclamps |04,

|05 and the bolts |06 against the respectively` associated annularshoulders |01 and |08 thereby forming inwardly of the diaphragm thesealed chambers |09 and 'Ihe tube l98 connects with the chamber while atube ||2 of corresponding function communicates with the chamber |09.Rlgidly secured to the diaphragm |03 v' is a post ||3 the outer end lofwhich extends around a pendulum contactor ||4. This ycontactor issuspended'byl a thin strip 5 of any suitable flexible material vsuchl assteel and is intended to permit the contactor to be held verticallynormally but capable of free movement in response to the motion of thediaphragm |03. A set screw H6 provided with a lock nut l I1 is advanceduntil its point just touches the side of the contactor. Should a slightleak in a can body cause adecrease in pressure in the small spaceimmediately surrounding the can body in the pocket as soon as theassociated can pocket tube 83 establishes communication with the tube 98through the recess 91 -this pressure decrease.

` tion of the pendulum contactor I9 and the mechanism associatedtherewith is identical with the construction of the mechanism associatedwith the contactor ||4, as is obvious upon inspection of Fig. 3. Thetubes 9.8 and ||2 and the corresponding recesses 91 and |2| are providedso thatv can bodies in the alternate pockets associated with aperturesI' and 80' may be tested and so thatif the can bodies are leah they mayAoperate in quick succession the necessary selector mechanism forseparating them from the good bodies. Fig. 7 shows diagrammatically theelectrical circuits employed for actuating the-magnet |22 which sets inmotion the selector mechanism. The recess 91 is provided with an offsetportion |23 so shaped that immediately following the reg-- istration ofanyaperture 88' with the recess 91 a second aperture |24 vwhich extendsthrough the movable plate 84 to the atmosphere will come intoregistration with the offset portion |23 of this continuous recess andrestorev atmospheric pressure to the chamber through the tube 9,8.Likewise the recess |2| has an offset portion |25 which will registerwith any of the apertures |26 following the registry of the precedingaperture 96 to restore atmospheric pressure to the cham- 20 ber |09inside' of the vdiaphragm |02. Restoration of atmospheric pressure tothe chambers |09 and will of course restore the associated pendulumcontacto'rs to their vertical position, inasmuch as the outside surfaceof each diaphragm is constantly exposed toatmosphericpressure.

The selector mechanism, just above referred to, for separating leaky canbodies from good can bodies does not form a part of the inventiondisclosed in this application but isfully described in my copendingapplication Serial No. 331,845, filed January 1l, 1929, being'illustrated particularly in Figs. 9, 15, 16, 17, 18, 19, 20, 21, 22, 23,24 ,and 25 thereof. Note that the magnet |22 shown in this applicationin Fig. 7 corresponds 35 in function and operation to the magnet |54 inmy prior application and the remainder of the mechanical equipment forseparating the good and bad can bodies is the same.

The mechanism for feeding can bodies intoV this 40 testing machine andthe mechanism for taking away both the good and the bad can bodies doesnot forml a part of this invention, and may be any suitable mechanism,being preferably that which is shown in my aforesaid copendingapplication.

The device operates as follows, briefly. As soonv as a' canals deliveredby the feed wheel up into position in front of a chuck 53 the suctiontube 46 associated with that chuck becomes rotated into a position whereit registers with the vacuum chamber 36, thus applying suction to thechuck which will thereupon grip the can pneurnatically at the same timethe segmental rack 62 will set into operation thev chuck reciprocatingmechanism and propel the can body into the associated can body pocket29. Illfhe space surrounding the can body will at this time be open toatmosphere 93 or 94. VImmediately thereafter the space sur- 60 roundingeach can body will be sealed from the atmosphere by the relativemovement of the plate# valves 84 and 81 and the vaculnn'being producedon the inside of the can body will begin to test the can body for leaks.Should the body be leaky the space surrounding the can body will haveits pressure resultingly decreased below atmospheric pressure and whenthe can pocket tube 83 registers either withthe recess 91 or |2| thisdecrease below atmospheric pressure will be transmitted to the properdiaphragm either |02 or |03 and close either the contact H8 or thecontact H8' to set in motion the selector mechanism, the latter beingfully described in my aforesaid copending application.

A modification of part of the invention is shown in Fig. 9. In thismodification, instead of applying vacuum to the inside of a can bodyposid tive pressure is applied through the passage |21 to the interioroi' the can body which is being held in a can pocket |23. The face oi.'the chuck |29 is provided with a resilient surface |3| made of rubber orsome suitable material for simultaneously sealing the open end oi' thecan body and the open end of the can pocket. In this instance a bottomplate |32 is provided in the pocket with fluted edges |33 whichestablish communication between the space outside of the can bodylaterally of the sides of the can and also at the bottom o! the can withthe passage |34. The plate |33 is movable, being normally urgedoutwardly from the bottom of the can pocket by compression springs |35which surround the guide pins |36, the latter being provided with heads|31. A can pocket tube |33 will connect the space surrounding each canbody to a passage, not shown, in the movable plate valve |39. 'I'hemovable plate valve and the stationary plate valve I4l are identical inconstruction with the plate valves 84 and Il heretofore described andthe functioning of these valves and their passages is the same. It isintended that the tubes |33 extending from these can pockets will beconnected to long and short passages in the movable plate valve just asisthe case in the foregoing described preferred embodiment. Hence twotubes |42 and |43 will lead from the stationary plate valve |4| and willcommunicate with the sealing chambers |44 and |45 which exist in theinside surface of the diaphragms |46 and |41. Obviously if.. a leakShould occur in a can body tested by this modifil cation the positiveinternal air pressure will raise the pressure in either chamber |44 or|45 and cause the diaphragms to be distended, swinging the associatedcontactors |48 or |49 outwardly to close the electrical circuits forenergizing the selector mechanism magnet. It will be apparent how thismodified portion of the invention cooperates with the remainder of thetesting machine without description thereof.

It should be understood that the invention herein disclosed issusceptible of embodiment in various modiiications within the spirit andscope of the appended claims.

Having shown and described my invention, I claim: Y

1. In a can body testing machine, the combination o! a movable carrierprovided with a series of testing receptacles each adapted to Vlooselyreceive a can body to be tested, means for introduclng a body into eachreceptacle, means for sealing each receptacle and the body therein toproduce a sealed chamber surrounding each body under atmosphericpressure, means for producing within the can body pressure other thanatmospheric pressure, a leak detecting mechanism comprising a pluralityof diaphragms each forming a closure for an air chamber, the outer faceoi each diaphragm being subjected to atmospheric pressure, conduit meansarranged to establish communication between each of said air chambersand alternate ones of said testing chambers and including a rotary valvecontrolling the establishment of such communication in predeterminedtimed relation, and means adapted to be actuated by either of saiddiaphragms, when pressure other than atmospheric is transmitted from atesting chamber to one'oi' said air chambers, whereby the leaky canAbody pressure, a leak detecting mechanism comprising a plurality ofdiaphragms each forming a l closure for an air chamber, the outer facevof each diaphragm being subjected to atmospheric pressure, conduitmeans arranged to establish communication between each of said airchambers and alternate ones of said testing chambers and including arotary valve controlling the establishment of such communication inpredeter- `mined timed relation, and means adapted to be a.

actuated by either or saidv diaphragms, when pressure other thanatmospheric is transmitted from a testing chamber to one oi' said airchambers, whereby the leaky can body in the chamber thus indicated isseparated from the remaining bodies. z3

3. In a' can body testing machine, the combination of a movable carrierprovided with a series of testing receptacles each adapted to looselyreceive a can body to be tested, means for sealing l each receptacle andthe body therein to produce 30 a sealed chamber surrounding each body,means for producing within the can body pressure other than atmosphericpressure, a leak detecting mechanism comprising a plurality ofdiaphragms each forming a closure for an air chamber, the 3S outer faceof each diaphragm being subjected to Vatmospheric pressure,l conduitmeans' arranged to establish communication between each of said airchambers and alternate ones of said testing chambers and including arotary valve control- 4o ling the establishment of such communication inpredetermined timed relation, said valve having provision fortemporarily opening each testing chamber to atmosphere after theestablishment of a non-atmospheric pressure within the 45 body disposedwithin said chamber, and means adapted to be actuated by either of saiddla- Dhragms when pressure other vthan atmospheric is transmitted from atesting chamber to one of said air chambers whereby the leaky canbody'50 in the chamber thus indicated is separated from the remainingbodies.

i. In a can body testing machine, the combination of a movable carrierprovided with a series of testing receptacles each adapted to 55 looselyreceive a can body to be tested, means for sealing each receptacle andthe body therein to. produce a sealed chamber surrounding each body,means for producing within the can body pressure other than atmosphericpressure, a leak 00 detecting mechanism comprising a plurality ofexpansible air chambers, conduit means arranged to establishcommunication between each oi said air chambers and alternate ones ofsaid testing chambers and including a rotary valve controlling @5 theestablishment of such communication in pre l determined timed relation,said valve being provided with means cooperating with said conduit meansfor venting each testing receptacle to atmosphere prior to theestabiishment oi' commu- 70 nication between such receptacle and saiddetecting mechanism, and means adapted to be actuated by either of saidair chambers, when pressure other than atmospheric is transmitted from atesting chamber to one o! said air cham 75 bers, wherebyfthe leaky canbody in the cham ber thus indicated is separated from theremainins'bodles.

5. Inca can body testing machine, the com- 5 bination of a movablecarrier provided with a series of testing receptacles each adapted toloosely receiving a can body to be tested, means for sealingeachreceptacle and the body therein to produce a sealed chambersurrounding each body under atmospheric pressure, means for producingwithin the can body pressure other than atmospheric pressure, a leakdetecting mechanism comprising a plurality of expansible air cham-Vindicated is separated from the'remaining bodies.

v WILLIAM CAMERON.

